Refrigerating apparatus



De.29, lesa L. A. PHlLiPP f 2,065,531-

REFRIGERATING APPARATUS original Filed Feb. 27, 193:5

INVENTOR. Lewes/wi: l?. PML/PP BY 4 W 2 M ATTORNEY.

Patented Dec. l2li), 1936 REFRIGERATING APPARATUS Lawrence A. Philipp,Detroit, Mich., assigner to Kelvinator Corporation, Detroit, Mich., acorporation of Michigan Application February 27, 1933, Serial No.

' Renewed July 15, 1936 1': claims. (ci. s2-12s) 'Ihis `inventionrelates -to refrigerating apparatus, and more particularly torefrigerating apparatus of the household type.

One of the objects of my invention is to provide a new and improvedarrangement for freezing substances and for cooling circulating air in arefrigerator cabinet.

Another object of my invention is to provide within a refrigeratorcabinet refrigerantevaporating means which is arranged and operatedwithout the collection vof frost thereon or a slight film of frost isallowed to collect thereon during the ori-phase of the refrigeratingcycle and is melted oil' during the off-phase of the refrig- -eratingcycle while at 'the same time provisions are made for freezingsubstances, such as ice cubes and the like, and for cooling circulatingair in the food storage compartment of the cabinet whereby continuousrefrigeration at substantially constant predetermined temperatures isassured and the necessity of periodic inoperative conditions of thesystem for defrosting is avoided.

Another object of my invention is to provide a new and improvedrefrigerant evaporator for cooling circulating air in a food storagecompartment of a refrigerator cabinet.

Other objects and advantages of the present invention will readily beapparent from the following description and by referring to theVaccompanying drawing. i

In the drawing:

Fig. 1 is a front view in elevation of a refrigerating apparatusembodying features of 'my invention;

Fig. 2 is a fragmentary, vertical view in cross section of the heat.absorbngmeans embodyingfeatures of my invention;

Fig. 3 is a side view in elevation of ther'elaf" tively small heatcapacity refrigerant evaporator forming part of the heat absorbingmeans;

Fig; 4 is a top plan view in elevation of the heat absorbing means;

Fig. 5 is a fragmentaryA View-in cross section and partly in elevationof a modied form of heat absorbing means; and

Fig. 6 is a View taken along the lin'e 6-6 of .Fig 5.

Referring to the drawing, the numeral 2ll'des1 ignates, in general, arefrigerator cabinet having a food storage compartment 2l. Within thefood storage compartment there is disposed heat absorbing meansdesignated, in general, by the numeral 23. A refrigerant Acondensingelement 25 is operatively connected to the heat absorbing means 23 bymeans of a liquid supply conduit 26` and a. vapor return conduit 21. Thecondensing element 25 may be located at any convenient place eitherwithin the cabinet or remote therefrom.

Referring more particularly lto Figs. 2,.3 and 4, theheat absorbingmeans 23 comprises, in general, a refrigerant evaporator 3D which is ofrelatively small heat capacity and which has a large areaexposed to thecirculating air within the food storage com- 10 partment 2l. Theevaporator 30 comprisesfin general, an outer metallic shell 32 which isof box-like construction and is provided with an open top which issecured to the top insulating wall33 of the food storage compartment by15 brackets 34 to prevent the admission of circulating air in the food,compartment into the interior of the shell 32. The shell 32 includesVertical in detail to the drawing, 'and 5` lside walls- 35, bottom wall31, rear wall 38 4and a front wall 40.l The front wall 4U is provided 2Dwith openings 42 of sufficient size for receiving ice making receptacles45. If desired, `the closure member or rear wall 38 may be omitted andthe shell 32 disposed in thefood storage compartment 2| adjacent therear wall thereof to 2'5 prevent circulation of 4air from the foodstorage compartment into the interior. of the shell 32. The evaporator30 also includes a pair of embossed sheetmetal plates 41, one of each.being secured to side walls 35 to provide spaces 48 and 30 49 forrefrigerant. Preferably, the embossed plates 41 are formed to provideserpentine-like passageways for refrigerant between its inner walland'theshell 32. The refrigerant spaces 48 and 49 between the plates 41and the sheet metal 35 shell 32 are inter-connected by means of arefrigerant conduit 50 which inter-connects said spaces adjacent thelower parts thereof. Liquid refrigerant is supplied to the refrigerantspaces from the liquid supply conduit 26', first into space 40 48 whenceit passes through conduit 50 into the refrigerant space 49. In order' toincrease the' heat transferV characteristics of the evaporator 30,

I have provided a plurality of U-shaped heat ab- These fins arevertically dis- 45 posed in parallel relation on each side of theevaporator adjacent thel refrigerant spaces V48 and`49. Preferably, theflns are welded to the shell 32.

VThe heat absorbing meansv 23' also includes a 50 relatively large heatcapacity refrigerant evaporator or low temperature evaporator which isdisposed entirely within the confines of the relativelysmall heatcapacity evaporator 30 so that its exposed surfaces will be exposed tosubstan- 55 'absorbing means.

tially non-circulating air. This arrangement either substantially orentirely avoids the necessity of periodically defrosting the4 lowtemperature evaporator 55. The low temperature evaporator 55 includes anouter sheet metal shell 51 and an inner sheet metal shell 5 8 suitablysecured together as by welding adjacent their edges and at variouscontacting points between the edges. These shells are formedsubstantially in the shape of a U and the outer shell being corrugatedas at 8| to provide spaces for the passage of refrigerant, between saidshells. The inner shell is provided with a pair of arcuate portions 82adjacent the upper opposite extremities thereof toprovide refrigerantheaders 83 for liquid and gaseous refrigerant. The headers 83 areinter-v connected by means of conduit 84 to which the vapor returnconduit 21 is connected. Liquid refrigerant is delivered to the lowtemperature evaporator 55 through a conduit 81 which is connected to theoutlet end of the relatively small heat capacity evaporator 30. Bothliquid and gaseous refrigerant passes from the evaporator 30 throughconduit 81 into the low temperature evaporator 55. The gaseousrefrigerant is withdrawn l'from the headers 83 and. conduit 84 throughthe vapor conduit 21. Suitable shelves 1| are provided within the icefreezing. zone 13 of evaporator 55 to support the ice trays 45.

The refrigerant condensing element comprises, in general, a compressor10, motor 12 for operating the compressor, condenser 14, and a high sidefloat mechanism 15. The compressor withdraws evaporated refrigerant fromthe heat absorbing means through conduit 21, compresses the gaseousrefrigerant and delivers it to the condenser wherein it is liquefied andfrom which it is delivered to the high side float mechanism. Liquidrefrigerant is supplied to the heat absorbing means through conduit 28under the control of float mechanism 15.- Preferably, the condensingelement is intermittently operated for maintaining substantiallyconstant predetermined temperatures in the heat In) order to control theoperation of the condensing element', I have provided an automaticswitch 80 which is actuated by expansible bellows B2 and a thermostaticuid containing bulb 85 in response to changes in temperatures in therelatively small heat capacity evaporator 30 for connecting anddisconnecting the motor to and from the power mains 81. Preferably, thebulb` 85 is soldered ,to a side wall of the evaporator 30 adjacent therefrigerant space 43. From the foregoing, it will be noted that the lowtemperature evaporator 55 is disposed within the confines of theevaporator 80 which is sealed to a wall of thefood storage compartment.Un-

der these conditions, none of the exposed surfaces` 'are arranged 4sothat the circulating air in the food compartment willcontact therewith.Only the substantially, non-circulating air within shell 1 32 cancontact with the low temperature evaporator. Thus, ,it is unnecessary totemporarily interrupt the normal cyclic operation of thecondensing-element to defrost the low temperature evaporator as theaccumulation of frost thereon is unlikely. Thus, insofar as the lowtemperature' evaporator isl concerned, continuous 4refrigeratiorf' of asubstantially constant predetermined value is assured.

In' order to avoid/ the necessity of interrupt-I ving the-refrigeratingeffect ofthe relatively small heat capacity evaporator, I have arrangedthe thermostaacauy controlled switch an so that the condensing elementis operated in such a manner that the demand for refrigeration by theevapoon its exposed surfacesdue to the deposit of moisture from thecirculating air. If desired, the switch may be set so that only a slightfilm of frost collects thereon during the on-phase of the refrigeratingcycle and is melted off during the olf-phase ofthe refrigerating cycle.B'y providng a relatively small heat capacity refrigerant evaporatorwhlc has a large area exposed to the circulating air, it may be operatedunder these conditions and maintain proper temperatures within the foodcompartment for the preservation of foods stored therein. Thus,continuous refrigeration of a substantially constant, predeterminedvalue in the evaporator 30 is assured. In an apparatus of the typehereinbefore described, the moisture contained in the circulating air isdeposited on the walls of the evaporator and whether the evaporator ispermitted to ac cmulate a slight film of frost between cycles or whetherit operates so that no frost forms thereon the temperature is low enoughto accumulate moisture on the side walls adjacent the spaces 48 and 48and on fins 5|. In order to carry off the drip water received from thefins 5| and sides 35 of evaporator 30, I have provided troughsimmediately below the fins 5| and at the lowermost parts of side walls35. Preferably, the troughs 90 are formed integrally with a sheet metalmember 92 which serves to clamp a slab of insulation 94 to the ,bottomWall/ 31 of the evaporator 30. This insulation prevents the deposit ofmoisture on the lowermost -part of the evaporator 30. Thus, it will benoted that the drip water from the side walls is taken care of bytroughs 90, and it will also be noticed that moisture is not de positedon the bottom wall of the relatively small heat capacity evaporator. Ifdesired, the troughs 80 may be interconnected by a conduit (not shown)which may be used for carrying olf the drip water to a suitable drain.

Referring now to Figs. 5 and 6, there is shown a modified form'of heatabsorbing means whichcom'prises, in general, a relatively small heatcapacity evaporator |00, which is constructed in all respects likeevaporator 30 and is operated under plied to evaporator |00 throughconduit |28, and

evaporated refrigerant is withdrawn from the up- 'permost plateevaporator |05 through conduit |21. Conduits '|28 and |21 correspond toconduits 28 and 21 and may be connected to the condensing element 25 ina like manner as conduits 28 and 21 are connected thereto. The plates 05are adapted for supporting ice trays and provide means for rapidlyfreezing the water in the trays.

From the foregoing, it will be apparent that I have providedrefrigerantv evaporating means which I have arranged in V,such a mannerthat itoperates without the collection of frost thereon or with a slightillm of frost collecting thereon only between cycles, while at the sametime provisions are made for freezing substances, such as ice cubes andthe like, and for cooling circulating air in the food storagecompartment of the cabinet whereby continuous refrigeration atsubstantially constant predetermined temperatures is assured and thenecessity of periodic inoperative conditions of the system fordefrosting is avoided. yInasmuch as the formation of a blanket of frostor ice onk the surfaces of an evaporator` acts as an insulating mediumto the transfer of heat, it will also be apparent from the foregoingthat the system described herein operates at maximum emciency andcontinuous refrigeration is furnished without interrupting therefrigerating effect of the heat absorbing means to free frost and icetherefrom.

Although onlya preferred form of the invention has been illustrated, andthat form described in detail, it will be apparent to those skilled inthe art that various modifications may be made therein without departingfrom the spirit of the invention or from the scope of the appendedclaims. i

What I claim as my invention is:

l. Refrigerating apparatus comprising, in combination, a cabinet havinga food storage compartment, a refrigerant evaporating element disposedin said compartment for cooling circulating air therein, a secondevaporating element for maintaining relatively low temperatures forfreezing substances, said second evaporating element being shieldedfromthe path of circulating air in the food storage compartment by saidfirst named evaporating element to prevent the deposit of moisture onsaid low temperature evaporating element from the circulating air, anintermittently operating refrigerant condensing element associated withsaid evaporating elements for maintaining said evaporating elementssubstantially flooded with liquid refrigerant, and means directlyassociated with said first named evaporating element for controlling theoperation of saidcondensing element, said means controlling the on andofi phases of the Vrefrigerating cycle in such a manner that frost doesnot accumulate on the rst named evaporating element at least part of thetime.

2. Refrigerating apparatus comprising a rela-l -evaporatoxs and meansdirectly responsive to changes in temperaturein said first namedevaporator for controlling said means.

3. Refrigerating apparatus comprising, in combination, a 'cabinet havinga food storage compartment, a box-like refrigerant evaporating elementhaving an open top secured to an insulated wall in said compartment,said evapo` rating element including an insulated bottom wall, afront'wall having an opening, means associated with each side wall toprovide spaces for` refrigerant, closure means. for the rear of saidelement and a refrigerant conduit interconnectying said side walls, arefrigerant evaporating element disposed within the confines of saidboxlike evaporating element arranged for receiving an ice makingreceptacle throughthe opening in the front wall 'of the box-likeelement, and means for supplying refrigerant to said elements.

4. A refrigerant evaporating element comprising a sheet metal shellincluding vertical walls and a bottom wall, one of said vertical wallshaving an opening of sufficient size to receive an ice makingreceptacle, an embossed sheet metal plate cooperating with one of saidvertical walls to provide a space for refrigerant, a second embossedsheet metal plate cooperating with an opposite wall to provide anadditional space for refrigerant, and a refrigerant conduitinterconnecting said spaces adjacent the lower parts' thereof.

5. A refrigerant evaporating element comprising a sheet metal shellincluding vertical walls and a bottom wall, one of said vertical wallshaving an opening of suincient size to Areceive anice makingreceptacle,an` embossed sheet metal plate cooperating with one of said verticalwalls t'o provide a space for refrigerant, a second embossed sheet metalplate cooperating with an opposite wall to provide an additional spacefor refrigerant, a refrigerant conduit interconnecting said spacesadjacent the lower parts thereof, and a relatively low temperaturerefrigerant evaporator disposed within said shell for freezing thecontents of said receptacle.

6. A refrigerant evaporating element comprising a sheet metal shellincluding vertical walls and a bottomwall, one of said vertical wallshaving an opening of sufficient size to receive an ice makingreceptacle, an embossed sheet metal plate cooperating with one vof saidvertical walls to provide a space for refrigerant, arsecond embossedsheet metal ,plate cooperating with an opposite wall to provide anadditional space for refrigerant, a relatively low temperaturerefrigerant evaporator disposed Within said shell for freezing thecontents of said receptacle, means for delivering liquid refrigerant toone of said spaces, a conduit interconnecting said spaces for deliveringliquid refrigerant from said space toV the other, means for carrying offliquid and gaseous refrigerant to the low ytemperature evaporator, andmeans for withdrawing exaporated refrigerant from the low temperatureevaporator.

'7. Refrigerating apparatus comprising, in combination, `a cabinethaving a food storage element having an' open top secured to a wall ofsaid compartment, said evaporating element including an insulated bottomwall, vertical walls, independent embossed plates cooperating only withthe two oppositeside walls to provide spaces for-refrigerant, arefrigerant conduit interconnecting said spaces at the lower partsthereof, fins on said side walls adjacent said plates, and troughsassociated with said elements for receiving moisture deposited from saidfins.

8.l Refrigerating apparatus comprising a refrigerant evaporatoradaptedto be positioned in a cabinet for cooling circulating air thereinand having a relatively large area exposed to the circulating air in thecabinet, a refrigerant evaporator disposed within the confines of thefirst named evaporator so as to be shielded from said l circulating air,a liquid refrigerant conduit .in-

terconnecting said evaporators for conducting liquid refrigerant fromone evaporator to the other, means for maintaining a substantiallyconstant quantity of liquid refrigerant in said compartment, a box-likerefrigerant evaporating evaporators, and a thermostat responsive tochanges in temperatures in said first named evaporator and arranged toso control said means as to operate the first named evaporator at leastpart of the time above a frost forming temperature and the secondevaporator constantly at a freezing temperature.

9. Refrigerating apparatus comprising a sheet metal shell having anopening in a wall thereof, a sheet metal member cooperating with asecond wall of said shell to provide a spacefor refrigerant, arefrigerant evaporator disposed within the confines of said shell andhaving provisions for receiving an ice' making receptacle through saidopening, means for maintaining a substantially constantle'vel of'liquidin said space for refrigerant and in said evaporator, andathermostatthermally associated with the refrigerant in said space for controllingsaid means. 1

10. A refrigerant evaporating element comprising a sheet metal shellincluding vertical wallsj and-a bottom wall, one of said vertical wallshaving an opening of sufilcient size to receive an ice makingreceptacle, sheet metal material cooperating with opposed vertical wallsto provide spaces for refrigerantga.refrigerant conduit interconnectinglsaid spaces, and a relatively low temperature refrigerant evaporatordisposed within said shell for freezing the contents of said receptacle.

11. A refrigerant evaporating element comprising a sheet metal shellincluding vertical walls and a bottom Wall, one of said vertical wallshaving an opening of suflicient size to receivelan ice makingreceptacle, sheet metal material cooperating with opposed vertical wallsto provide spaces for refrigerant, a refrigerant conduit interconnectingsaid spaces, a low temperature refrigerant evaporator disposed withinsaid shell for freezing the contents of said receptacle, and insulatingmaterial associated with said bottom wall.

12. Refrigerating apparatus comprising, in combination, a cabinet havinga food storage compartment, a box-like refrigerant evaporating elementconstructed 'of sheet metal material and having an open top secured toan insulated wall in said compartment, said evaporating element havingan open front, sheet metal means associated with opposed side walls toprovide spaces for refrigerant; a refrigerant evaporating elementdisposed within the confines of said boxlike element and being arrangedfor receiving an ice making receptacle through said open front of thebox-like element, and means for supplying refrigerant to said elements.

13. Refrigerating apparatus comprising,v in combination, a cabinethaving a food storage compartment,`a box-like refrigerant evaporatingelement constructed of sheet metal materialand having an open topsecured to an insulated wall provide spaces for refrigerant, and icetray, heat.

absorbing means disposed within the confines of said element and, beingarranged for supporting said. ice tray, a tray front secured tosaidtray, said tray front being arranged to close said opening whensupported by said means, and means for supplying refrigerant to saidelement and heat absorbing means.

14. yRefrigerating apparatus comprising, in

, said second element as rapidly as the first named element, means fordelivering liquid refrigerant rst to said first named element and thenboth liquid and gaseous refrigerant from said first element to saidsecond element, and thermostatic means associated .with said firstelement for controlling the operation of said apparatus in such amannerthat frost does not accumulate on said first element at least partof the time.

15. A refrigerating system of the flooded type comprising a refrigerantevaporating element adaptedto be positioned in a compartment for coolingcirculating air, a second refrigerant evaporating element for freezingsubstances, a refrigerant condensing unit associated with saidAelements, a high side float mechanism for controlling the flow ofrefrigerant to saidflrst element, conduit means for conducting vthe flowof both liquid and gaseous refrigerant to the second element after therefrigerant haspassed through said first element, and means directlyresponsive to the conditionA of said first element for controlling theoperation of said condensing unit.

16. Arefrigerating system of the flooded type comprising a refrigerantevaporating element adapted to be positioned in a compartment forcooling circulating air, a second refrigerant evaporating element forfreezing substances, a refrigerant condensing unit associated with saidelements, mechanism for controlling the flow of refrigerant to saidfirst element, conduit means for conducting the flow of both liquid andgaseous refrigerant to the second element after the refrigerant haspassed through said first element, and means directly responsive to thecondition of said first element for controlling theoperation of saidcondensingunit.

17. A refrigerant evaporatingA element of the type adapted to bepositioned in a compartment for cooling circulating air therein,comprising refrigerant containing walls exposed to the circulating airin the compartment and a bottom wall insulated so that cooling of thecirculating air is accomplished only by said other walls.

LAWRENCE A. PHILIP?.

